Heavy organic vapors (such as hydrocarbons, phthalates, adipates, fatty amines and phenols), corrosive inorganic gases (such as hydrogen chloride, hydrogen sulfide, sulfur dioxide, nitrogen oxides and ammonia) and particles comprise the major contaminants of disc drive data storage systems. Organic vapors and corrosive gases can induce smears on head and disc surfaces, corrode magnetic devices and other metallic components, while particles can either scratch or get embedded into various drive components, causing the drives to fail. Current disc drives are more susceptible to these contaminants because of the many material changes inside the drives required to respond to the need for higher recording density.
Most current disc drives use two separate filters; a particle filter packed with polymer fibers and a chemical filter including active-carbons. It is well known that a life span of a chemical filter including active-carbon is limited by its surface area for adsorption. With the continuing tendency to increase areal densities of disc drives and to reduce their size, having an independent particle filter and a separate relatively small chemical filter, with a relatively limited surface area for adsorption, may result in potential susceptibility to contaminants and insufficient space to hold them properly inside a drive. In general, decreasing the form factor of a drive necessitates reducing the footprints of components within the drive and therefore separate particle and chemical filters may not be suitable for use in drives with a reduced form factor.
Embodiments of the present invention provide solutions to these and other problems, and offer other advantages over the prior art.